Failover for SQL lookup expansions?

[Brian Candler]

Phil Mayers wrote:
> Correct. Virtual modules (e.g. "redundant") do not implement the "xlat"
> function.
...
> Unfortunately the "xlat" functions in FR don't return error/success codes.
> They return "length of result string", and 0 for any failure condition,
> which means it's impossible to distinguish a failure from an empty result,
> and also that you can't use "if (ok)" constructs.

OK, thanks for that. I wonder if it would be worth coding for this, e.g.
return -1 for fail? (although that would break everything which blindly uses
it as length of string :-)

It does seem that some string expansions fail silently at the moment, which
could perhaps do with being a bit more strict. e.g. I once wrote
    "%{Reply:AttrName}"
instead of
    "%{reply:AttrName}"
and it produced nothing more than a 'Warning' at freeradius -X.

> You will probably need something like this:
> 
> update request {
>   Attrib := "%{sql1:select ...}"
> }
> if (!Attrib) {
>   update request {
>     Attrib := "%{sql2:select ...}"
>   }
> }

Thank you. I'll see what I can do.

Regards,

Brian.